Re: [PATCH 1/3] KVM: nVMX: Fix virtual interrupt delivery injection

Wanpeng Li
2014-07-17T09:10:50Z

On Thu, Jul 17, 2014 at 09:03:01AM +0000, Zhang, Yang Z wrote:
>Paolo Bonzini wrote on 2014-07-17:
>> Il 17/07/2014 06:56, Wanpeng Li ha scritto:
>>> This patch fix bug reported in
>>> https://bugzilla.kernel.org/show_bug.cgi?id=73331, after the patch
>>> http://www.spinics.net/lists/kvm/msg105230.html applied, there is some
>>> progress and the L2 can boot up, however, slowly. The original idea of
>>> this fix vid injection patch is from "Zhang, Yang Z"
>>> <yang.z.zhang@intel.com>.
>>>
>>> Interrupt which delivered by vid should be injected to L1 by L0 if
>>> current is in L1, or should be injected to L2 by L0 through the old
>>> injection way if L1 doesn't have set VM_EXIT_ACK_INTR_ON_EXIT. The
>>> current logic doen't consider these cases. This patch fix it by vid
>>> intr to L1 if current is L1 or L2 through old injection way if L1
>>> doen't have VM_EXIT_ACK_INTR_ON_EXIT set.
>>>
>>> Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
>>> Signed-off-by: "Zhang, Yang Z" <yang.z.zhang@intel.com>
>>> ---
>>> arch/x86/kvm/vmx.c | 18 ++++++++++++++++--
>>> 1 file changed, 16 insertions(+), 2 deletions(-)
>>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index
>>> 021d84a..ad36646 100644
>>> --- a/arch/x86/kvm/vmx.c
>>> +++ b/arch/x86/kvm/vmx.c
>>> @@ -7112,8 +7112,22 @@ static void vmx_hwapic_irr_update(struct
>>> kvm_vcpu *vcpu, int max_irr) {
>>> if (max_irr == -1)
>>> return;
>>> -
>>> - vmx_set_rvi(max_irr);
>>> + if (!is_guest_mode(vcpu)) {
>>> + vmx_set_rvi(max_irr);
>>> + } else if (is_guest_mode(vcpu) && !nested_exit_on_intr(vcpu)) {
>>> + /*
>>> + * Fall back to old way to inject the interrupt since there
>>> + * is no vAPIC-v for L2.
>>> + */
>>> + if (vcpu->arch.exception.pending ||
>>> + vcpu->arch.nmi_injected ||
>>> + vcpu->arch.interrupt.pending)
>>> + return;
>>> + else if (vmx_interrupt_allowed(vcpu)) {
>>> + kvm_queue_interrupt(vcpu, max_irr, false);
>>> + vmx_inject_irq(vcpu);
>>> + }
>>> + }
>>> }
>>>
>>> static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64
>>> *eoi_exit_bitmap)
>>>
>>
>> What hypervisor did you test with? nested_exit_on_intr(vcpu) will
>
>Jailhouse will clear External-interrupt exiting bit. Am I right? Jan.
>
>> return true for both Xen and KVM (nested_exit_on_intr is not the same
>> thing as ACK_INTR_ON_EXIT).
>
>I guess he want to say External-interrupt exiting bit not ACK_INTR_ON_EXIT.
>

Ah yes, a typo here.

Regards,
Wanpeng Li

>>
>> Paolo
>
>
>Best regards,
>Yang
>